import re

from django_redis import get_redis_connection
from rest_framework import serializers
from rest_framework_jwt.settings import api_settings

from celery_tasks.email.task import send_active_email
from users.models import User


class CreateUsersSerializer(serializers.ModelSerializer):
    """创建用户序列化器"""
    password2 = serializers.CharField(label="确认密码", write_only=True)
    sms_code = serializers.CharField(label="短信验证码", write_only=True)
    allow = serializers.CharField(label="同意协议", write_only=True)
    token = serializers.CharField(label="JWT token", read_only=True)

    class Meta:
        model = User
        fields = ("id", "username", "password", "password2", "sms_code", "mobile", "allow", "token")
        extra_kwargs = {
            'username': {
                'min_length': 5,
                'max_length': 20,
                'error_messages': {
                    'min_length': '仅允许5-20个字符的用户名',
                    'max_length': '仅允许5-20个字符的用户名',
                }
            },
            'password': {
                'write_only': True,
                'min_length': 8,
                'max_length': 20,
                'error_messages': {
                    'min_length': '仅允许8-20个字符的密码',
                    'max_length': '仅允许8-20个字符的密码',
                }
            }
        }


    def validate_mobile(self, value):
        """验证手机号码"""
        if not re.match(r"^1[3-9]\w{9}$", value):
            raise serializers.ValidationError("手机号格式错误")
        return value

    def validate_allow(self, value):
        """检验用户是否同意协议"""
        if value != "true":
            raise serializers.ValidationError("请同意协议")
        return value

    def validate(self, data):
        # 判断两次密码
        if data["password"] != data["password2"]:
            raise serializers.ValidationError("两次密码输入不一致")

        # 判断短信验证码
        redis_conn = get_redis_connection("verify_codes")
        mobile = data["mobile"]
        real_sms_code = redis_conn.get("SMS_%s" % mobile)

        if real_sms_code is None:
            raise serializers.ValidationError("无效的短信验证码")

        if data["sms_code"] != real_sms_code.decode():
            raise serializers.ValidationError("短信验证码输入错误")

        return data

    def create(self, validated_data):
        """创建用户"""
        # 移除数据库模型类中不存在的属性
        del validated_data["password2"]
        del validated_data["sms_code"]
        del validated_data["allow"]

        user = super().create(validated_data)

        # 调用django的认证系统加密
        user.set_password(validated_data["password"])
        user.save()

        # 签发
        jwt_payload_handler = api_settings.JWT_PAYLOAD_HANDLER
        jwt_encode_handler = api_settings.JWT_ENCODE_HANDLER

        payload = jwt_payload_handler(user)
        token = jwt_encode_handler(payload)
        user.token = token

        return user


class UserDetailSerializer(serializers.ModelSerializer):
    """用户详细信息序列化器"""

    class Meta:
        model=User
        fields=('id','username','mobile','email','email_active')


class EmailSerializer(serializers.ModelSerializer):
    class Meta:
        model=User
        fields=('id','email')

    def update(self, instance, validated_data):
        """

        :param instance: 视图传过来的user对象
        :param validated_data:
        :return:
        """

        email=validated_data['email']

        instance.email=email
        instance.save()

        # 生成激活链接
        url=instance.generate_verify_email_url()

        # 发送邮件
        send_active_email.delay(email,url)

        return instance
